I. Field of the Invention
The present invention is directed to a control module employed to control the operation of the passenger compartment heating/cooling system of an automotive vehicle.
II. Description of the Related Art
In a typical present-day automotive heating/cooling system, a ducting system is provided with air flow directing doors which, by a control system, may be set selectively to supply heated air, cooled air from an air conditioner, or fresh outside air to the passenger compartment through discharge openings which direct the flow of air to the windshield and to other discharge openings which may discharge air from the dashboard and the floor. The control panel allows a selection of any of several different operating modes. Typically, positioning of the various doors or deflectors which control the path of air flow through the duct system is accomplished by a vacuum actuated motor which is selectively connected either to a vacuum source or to atmospheric vent by a solenoid controlled valve. A typical system will require four or more doors, each of which must have a solenoid valve to control actuation of its positioning vacuum motor. In addition to electrical circuitry for controlling energization and deenergization of the various solenoid valves, the system will require electrical control circuitry for controlling operation of the blower motor which induces the flow of air through the duct system and also circuitry and controls for controlling operation of the clutch associated with the air- conditioning compressor.
The operating controls for such systems typically take the form of electrical switches which must be mounted at a location within the reach of the driver of the vehicle, normally at the center of the dashboard at a location accessible both to the driver and to a front seat passenger. The increasing complexity and general down sizing of motor vehicles has drastically reduced the space available, particularly in the passenger compartment, for the mounting and installation of various components. As is always the case with automotive components, ease of installation on the assembly line is a prime consideration.
Thus, for a component, such as the heating/cooling system control system, a compact modular package is desirable. However, a compact, box-like control module which is capable of being installed in the vehicle simply by slipping it into place must in turn be so designed that it may itself be easily assembled because of the large number of such modules which must be produced. Ease of assembly is not always compatible with the achievement of a tight assembly, an important consideration in automotive applications where the assembled device is subject to vibration and jolting inherent in the normal operation of the vehicle.
The climate control system control module of the present invention is directed to the solution of the foregoing problems.